Inclusion Criteria:

        Adult men & women ≥ 18 years of age Histologically confirmed advanced malignancies with
        documented progression following standard therapy, or for whom, in the opinion of the
        investigator, no appropriate standard therapy exists.

        Must have a site of disease amenable to biopsy and be a candidate for tumor biopsy
        according to the treating institution's guidelines. The patient must be willing to undergo
        a new tumor biopsy at screening and during treatment.

        ECOG performance status 0-2 and in the opinion of the investigator, likely to complete at
        least 56 days of treatment.

        Exclusion Criteria:

        Symptomatic or uncontrolled Brain metastases requiring concurrent treatment, inclusive of
        but not limited to surgery, radiation and/or corticosteroids.

        Patients with treated symptomatic brain metastases should be neurologically stable for 4
        weeks post-treatment prior to study entry and at doses of <10 mg per day prednisolone or
        equivalent for at least 2 weeks before administration of any study treatment.

        Patients who required discontinuation of treatment due to treatment-related toxicities with
        prior immunotherapy.

        Patients previously treated with anti-CD73 treatment and/or adenosine receptor A2a (A2aR)
        inhibitors.

        Active, previously documented, or suspected autoimmune disease within the past 2 years.

        Patients with vitiligo, type I diabetes, residual hypothyroidism only requiring hormone
        replacement, psoriasis not requiring systemic treatment or conditions not expected to recur
        should not be excluded. Additionally, patients previously exposed to anti-PD-1/PD-L1
        treatment who are adequately treated for skin rash or with replacement therapy for
        endocrinopathies should not be excluded.

        History of or current drug-induced interstitial lung disease or pneumonitis grade ≥ 2.

        Impaired cardiovascular function or clinically significant cardiovascular disease,
        including any of the following: Clinically significant and/or uncontrolled heart disease
        such as congestive heart failure requiring treatment (NYHA Grade ≥ 2), uncontrolled
        hypertension or clinically significant arrhythmia Patients with corrected QT using the
        Fridericia's correction (QTcF) > 470 msec for females or >450 msec for males, on screening
        ECG or congenital long QT syndrome Acute myocardial infarction or unstable angina < 3
        months prior to study entry History of stroke or transient ischemic event requiring medical
        therapy Symptomatic claudication Infection: HIV infection, Active HBV or HCV infection (per
        institutional guidelines). Patients with chronic HBV or HCV disease that is controlled
        under antiviral therapy are allowed in the expansion but not in the escalation, Known
        history of tuberculosis Infection requiring systemic antibiotic therapy. Patients requiring
        systemic antibiotics for infection must have completed treatment before screening is
        initiated.

        Systemic anti-cancer therapy within 2 weeks of the first dose of study treatment. For
        cytotoxic agents that have major delayed toxicity, e.g. mitomycin C and nitrosoureas, 6
        weeks is indicated as washout period. For patients receiving anticancer immunotherapies, 4
        weeks is indicated as the washout period.

        Systemic chronic steroid therapy (≥ 10 mg/day prednisone or equivalent) or any
        immunosuppressive therapy, other than replacement dose steroids in the setting of adrenal
        insufficiency, within 7 days of the first dose of study treatment. Topical, inhaled, nasal,
        and ophthalmic steroids are allowed

        Other protocol-defined inclusion/exclusion criteria may apply